(EDITORIAL NOTE- While I researched this subject, I do NOT mean this posting to be a scientific manifesto on the current COVID-19 pandemic. It's background information for the fictional world of Rosella Tolfree and nothing more.)
Dry Virus Propagation
Certain viruses prefer dry or low humidity levels for propagation.
Such low humidity levels create smaller aerosol particles. Typical particle size is less than one micron in size.
With COVID-19, it overwhelms the lungs because of the penetration of small particles into tracheobronchial mucus layers and interacting with that tissue. This is besides the alveolar interactions. Since COVID-19 is new to the human species, the immunological response can be overactive.
Unlike MERS and SARS, COVID-19 lingers in the human body before symptoms appear, allowing individuals to easily spread this contagion. Both MERS and SARS rapidly killed the host, lowering the chance of infectious spread.
Even infection of the eyes from infected surfaces can become a serious problem with such new viruses. Research shows that respiratory viruses can travel from the eyes to the lungs, but how is unclear. Lung infection levels maybe be less according to some studies. But with a novel virus, even a minor lung infection can become a serious reality.
Typically, the routes to the eyes and mouth are from touching fomites, or ordinary items, that contain the virus. Some viruses can live a long time on objects because of their capsid, or outer protective shell. There are viruses which can enter the human body through the skin itself once touched, but respiratory viruses do not work this way.
The spread of dry loving viruses through the air is complex, involving vapor pressure to effects of gravity. With such a small particle size, the ability to travel across large rooms is possible. Based on one study, it’s possible that HVAC systems could circulate small particles throughout a building complex and infect that building’s population. Other studies have shown the presence of coronaviruses on internal HVAC parts. Submicron filtration systems in HVACs can reduce these problems. But this filtration comes at greater energy costs due to the greater force required to propel air through the filters.
Immunological Response and Reservoirs
Typical immunological response to “cold viruses” results in the destruction of tissue, and with such widespread destruction those who are already “compromised” can die easily from secondary pneumonias.
Roughly 80% of these sized particles are normally breathed out by the human body based on an influenza study, and it’s reasonable to assume the same is true for the coronavirus family. The exact quantity of viral shedding will vary from person to person.
This allows for reservoirs of humans to develop in communities, especially in “healthy” younger populations where reinfection rates can occur multiple times a year.
People will build up antibody resistance through exposure. But this antibody resistance fades over the course of a year, requiring constant reinfection to maintain resistance. This explains why today there’s annual influenza shots.
A very few people may have a “natural immunity” caused by the fact the virus cannot enter a person’s cells for reproduction. This is because the person lacks certain access mechanisms on their cells. But this is not the norm and is a rarity. Although with CRISPR technologies, it may be possible to build humans with more natural immunity. Except usually there’s a tradeoff with such concepts. So, while the person is immune to some virus, some other cellular problem may happen. Thus, crippling the individual.
The Future Wetter World of Rosella Tolfree
In high humidity situations, the particle density would drop. Therefore, equatorial regions tend not to see coronavirus, influenza and RSV infections as much as northern and southern latitudes. Typically, locations seeing less than 50% humidity may see outdoor spread in greater amounts depending upon such factors as density of population centers, availability of people to congregate outside, and general weather patterns.
With Rosella Tolfree’s world, which has warmer atmospheric conditions, these dry viruses are less likely. The propagation of influenza and cold viruses in a world, with global warming and melted ice caps, would be confined to areas where human occupation is confined in buildings. The spread would be limited and only as pockets in certain city areas.
With increased humidity because of warmer atmospheric conditions, molds and high humidity loving viruses, which lack an envelope like rhinovirus, poliovirus, and picornavirus, will be more common atmospheric contagions.
There’s the possibility of a pollen attaching virus from flowering plants to infect humans. This could be a likely adaptive mutation of one of the dry viruses into a new vector and transmission source. We know bats are pollinators for certain flowers along with being nectar drinkers. It’s possible that one of the many bat-type coronaviruses could mutate into a pollen clinging strain. This assumes that bats as a species survive the Great Melt and a sub-species adapts to a wider range of flowering diet. If humans helped this by transplanting tropical and other subtropical species of plants to replace the loss of colder varieties, then this could speed up the possibilities of this new contagion.
During the actual Great Melt, most pandemics will be older ones because of the breakdown of water purification systems and general health networks. Standard bacterial infections of cholera and viral infections of measles due to low population inoculation would become more commonplace.
Improved Future Technology
One of the major technological breakthroughs prior to the Great Melt was the development of 3-D printing on a molecular scale. Not only did this allow the 3-D printing of cellular materials, such as a human zygote, but also the manufacturing of artificial viral vaccines. In Rosella Tolfree’s time, viral vaccinations are easily printed and replicated in mass thanks to stable RNA chains. This caused many “common cold” and respiratory viruses to be eliminated from the human population prior to the Great Melt. The problem is the time after the Great Melt, nations went into political isolation causing an increase in older health pandemics. So, while the viral vaccination technology is present, by the later time periods its availability became limited to certain peoples of society.
The warmer, slightly more humid world of Rosella Tolfree has made coronaviruses and influenza something of the past. But the trade off has been the recurrence of older pandemics due to the global collapse of infrastructure and national isolationism.
Combined Image Citation
Dark Skies in Death Valley, By Joe Mania, Source Unsplash
This illustration provided a 3D graphical representation of a number of Rotavirus virions, set against a black background. Note the organism’s characteristic, wheel-like appearance, which was made visible when viewed under the electron microscope. It’s this morphology that gives the Rotavirus its name, which is derived from the Latin rota, meaning "wheel". Rotaviruses are nonenveloped, double-shelled viruses, making them quite stable in the environment. By CDC, Source Unsplash
Seth Underwood writes hard science fiction and political dystopian science fiction. His future political dystopian U.S. world features decades of despot presidents, a flooded world, and new para-military force known as the Ranger Marshals. He has freemium stories at www. sethunderwoodstories.com